Die.



No. '680,448.- Patentad Aug. I3, I90I. J. B. WALLACE, Decd.

F. E, WALLACE, flflminiatratrix.

DIE

(Apphcation filed. m 15, 1900) (In lfllel.) I

WITNESSES:

UNITED STATES PATENT OFFICE.

JACOB B. WALLACE, OF ERIE, PENNSYLVANIA; FLORENCE E. WALLACE, AD-

MINISTRATRIX OF SAID JACOB B.

WALLACE, DECEASED, ASSIGNOR, EY

MESNE ASSIGNMENTS, TO MODERN TOOL COMPANY, OF SAME PLACE.

one.

'sPEcIFfcArmN fonning' part of Letters Patent No. 680,448, dated August 13, 1901.

Application filed May 16 1900.

To all whom it may concern:

Be it known that I, J AOOB B. WALLACE, a citizen of the United States, residing at Erie, in the county of Erie and State of Pennsylvania, have invented certain new and useful Improvements in Dies; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it ap- 1O pertains to make and use the same.

This invention relates to dies and it consists in certain improvements in the construction thereof, as will be hereinafter fully described, and pointed out in the claims.

More particularly, the invention relates to that class of dies which are adjustable and self-opening.

The invention is illustrated in the accompanying drawings, as follows:

Figure 1 shows a front elevation of the die. Fig. 2 showsa section on the lines 2 2 3 3 in Fig. 1.

A marks the shank on which the device is mounted. This shank is preferably mount 2 5 ed in the turret of a screw-machine. In the face of the shank A there is a bearing A, in which is journaled the head B. On the face of the head are arranged a series of guideways B, in which are the grooves 12. The chasers C are mounted on the blocks F. These blocks are provided with the tongues f, which fit in the grooves. The chasers are moved to and from the work by movement of the blocks in the guideways B. The cam-ring D is mounted on the outer or bearing surface A of the shank A. The front part of the cam-ring is provided with the cam-surfaces d, which are arranged to operate upon the cam-surfaces f of the blocks F. Each of the blocks is provided with a radial opening f, closed at the outer ends by the screw-plug f Opening into this radial openingis the slot J. A screw f extends from the head B through the slot f into the radial opening f A spring f is tensioned against the head of the screw f and the screw-plug f This spring presses the block against the cam-surface d, so that when the cam-ring is moved around to bring the cam-surface at out of register with the camscrew 01 Serial No. 16 ,820. (No model.)

surface f the blocks F are moved outwardly, 0 so as to move the chasers C out of operative position. v

Arranged on the face of the head B is a circumferential groove b. A screw d extends from the cam-ring D into this groove and locks 5 5 the cam-ring against axial movement on the head. A screw 11 is secured to the head in the groove b. A spring d extends from the screw d to the screw 12 and, tends to rotate the cam-ring D to throw the cam-surfaces d '60 out of register with the cam-surfaces f, so as to allow the springs f to open the die.

Arranged in a slot 61 in the under side of thecam-ring is an adjusting-block D. Extending from this adjusting-block D is a set- 65 This set-screw extends throngh'a slot (1 in the cam-ring. By loosening the set-screw the block D may be moved circumferentially on the cam-ring. Arranged in this block is a groove (1, which extends in an axial direction along the face A of the shank.

Arranged on the shank is a lug a. This log is of asize which will permit of its entry into the groove d A handle D is provided for rotating the cam-ring. An opening 6 extends into the face of the head B and is extended by a smaller opening 12 through the head. A screw G extends through the openings and b and is screwed into the shank.

The head g of this screw forms a sliding fitin the opening b back of the head g. This spring tends to hold the flange of the head: in contact with the shank A.

The operation of the device is as follows: The cam-ring is rotative until a lug a is brought into register with the groove d. The tension of the spring Hthen snaps the head back into contact with the shank A, carrying the lug a, into the groove 01 thus 0 locking the cam-ring in the set position. The cam-ringin itsset positionbrings the camsurfaces d into register with the cam-surfaces f, so as to press the blocks F to the inner position desired. The die is then fed onto 5 the work until the turret arrives at its provided stop, (not shown,) which determines the length of the screw. The work continuin the opening 19 A spring H is arranged position and the spring f 5 snaps the blocks to V This allows the turret to be moved back, carrying the dies away' their open position.

from the work. In the ordinary operation of these devices a lug D is provided, which contacts that part of the machine, so as to turn the cam-ring to its set position with a movement of the turret. With this construc-.

tion the cam-surfaces are exactly in line of the strain on the chasers, so that any beli- -crank action is avoided. By this arrangement there is no springing of the device,- and consequently when the device is once ad-- justed it continues to cut threads of exactly the same'size, so that they may be used interchangeably whatever diffierence there may be in the quality of the material operated upon. This is a very important feature where dies are used for making interchangeable work or where a continuous standard gage is desired.

It will be noted that the cam-surfaces up to the moment of release of the chasers cover the entire surfaces of the chasers subjected to strain, so that there is no tendency to bellcrank action, and consequently an even thread is prod need. This is accomplishedin the present device by giving to the cam-surfaces a rotative movement, with the axis of the head as a center. In this way the camsurfaces are moved over the chasers throughout their width at the same time. It will be noted also that the chasers are held to their work until the head has reached a predetermined point, when they are immediately opened by the spring (1 so that the thread produced is of exactly the same depth throughout its length. From this it will be seen that by preventing bell-crank action and holding the chasers to their work until released a thread of the same size throughout its length can be produced, if desired.

What I claim as new is 1. In a die, the-combination of a carrier; a head mounted on said carrier; chasers carried by said head; cams for moving said chasers to their work, and for locking said chasers in their set position, said cam-surfaces being arranged in the line of strain on said chasers; means for automatically moving said cam-surfaces to release said chasers from their set positions at a predetermined point; said means being arranged to operateafter being brought into action independently of the movement of the head; and springs operating independently of the cams arranged to open said chasers when released by the cam.

2. In a die, the combination with a carrier A; the head B slidingly mounted thereon and having guides therein; chasers carried by said guides; the cam-ring D arranged 'to have r0- tative movement on the head and having the cam-surfaces darranged in line with the strain on the chasers; a spring mechanism operating independently of the cams for opening said chasers when released by the cam; means for locking the cam in the set position; and means for releasing the said locking mechanism when the head D is moved away from the shank or carrier A.

3. In a die,the combination with the carrier, A; the head, B, slidingly mounted thereon and having the guides for the chaser-block; the blocks, F, mounted in said guides; chasers arranged in said blocks; the cam-ring, D, arranged to have rotative movement with the ax'isot the head as a center, having the camsurfaces, d, arranged in line with the strain on the chasers; aspring mechanism for opening said blocks when released by the cam; said spring mechanism being independent of the cam; means for locking the cam in a set position; and means for releasing said looking mechanism when the head, B, is moved away from the shank or carrier, A.

4. In a die, the combination of the shank, A the head, B; mounted thereon, having the openings, b and b therethrough; 'circum ferential grooves, 12, therein-,- and the guides,- B, therein 5 the blocks, F, arranged in the guides, B, said blocks being provided with the opening, f and slot, f the spring, H, arranged in the opening, 12 the spring, f being arranged in the opening, f the camriug, D, having thecam-surfaces, d, therein; a spring (1 arranged in the circumferential slot, b, and tensioned between the cam-ring and the head to rotate the cam-ring in a direction to open the die; a groove-and-lug mechanism arranged between the cam-ring and the shank and arranged to be brought out of engagement by an axial movement of the head on the shank.-

5. In a die, the combination of the shank, A; the head, B, mounted thereon, having the openings, 6 and-b therethrough circum ferential grooves, 19, therein; the guides, B, therein; the block, F, arranged in the guides, B, said blocks being provided with the openings, f andslot, f the spring, H, arranged in the opening, b the spring, f arranged in the opening, f; the cam-ring, D, having the cam-surfaces, d, thereon; a spring, d arranged in-the circumferential slot, 1), and tensioned between the cam-ring and the head to,

rotate the cam-ring in a direction to open the die; a groove-block arranged on said cam 5 means for adjusting said block; a lugon the shank adapted to register and enter said groove when the cam is moved to a set position, and to be thrown out of saidgroove by an'axial movement of the head relatively to the shank.

6. In a'die, the combination of a carrier; a head mounted on said carrier; chasers carfor moving said cam-ring away from said 111g, a, and by said lug, a, to disengage the chaser. to

In testimony whereof I affix my signature in presence of two witnesses.

JACOB B. WALLACE;

. Witnesses:

R. F. LANZA,: 1'1. 0. LORD; 

